Method of making insoles



July 28, 1942. F L, AYERS 2,291,017

METHOD OF MAKING INSOLES FiledMarch 7, 1941 Patented July 28, 1942 UNITED STA-TES PATENT oFFIcE METHOD F INSOLES Fred L. Ayers, Watertown, Mass., assignor, by mesne assignments, to Reconstruction Finance Corporation, Washington, 11C., a corppration 'of States of America Application March 7, 1941, Serial No. 382,115

(Cl. ll)

2 Claims.

This invention relates -to an insole and a method of making the same. '-It deals more'especially with an insole `whose ball zone or area is prepared for the reception of a` pad of resiliently compressible material, such as sponge rubber, cork composition, or the like, which increases the comfort or cushioning property of the shoe at the particular Zone or area at which the foot bears with the greatest pressure.

`In accordance with the present invention, the forepart ofthe insole is perforated at the ball zone at preferably substantially regularly spaced intervals to afford multiplicity of openings or voids and the perforated Zone then subjected to sufficient compaction, as in the die-press, to cause a substantial reduction in thickness of such zone and the attendant creation of a concavity or shallow thereat as material or insole stock in the spaces intervening between the openings is squeezed or caused to be displaced into the openings and to close them. It is preferable to carry the compression or compaction to a stage short of closing the openings, since they are desirable for ventilation purpose. The method hereof is applicable to various kinds of insole stock, including not only natural leather but also various leather substitutes. It is applicable to especially good advantage to an artificial leather composed essentially of a felted fibrous web, such as a web made on a papermaking machine from refined Wood pulp (Solka or Cellate pulp), and impregnated with a suitable rubber composition, such as rubber latex composition. Such an articial leather is characterized by relatively ready compressibility such as comports with the desired compression or compaction of the insole forepart at the ball zone or area.

With the foregoing and other features and objects in view, the present invention will now be described in further detail with particular reference to the accompanying drawing, wherein,

Fig. 1 represents in plan view an insole containing the initial relatively large periorations at its forepart. Y

Fig. 2 is a transverse section through the forepart on the line 2-2 of Fig. l.

Fig. 3 shows the insole forepart after the perforated Zone has undergone compression or compaction.

Fig. 4 is a transverse section through the forepart on the line 4--4 of Fig. 3.

Fig. 5 shows in perspective a cushioning pad or filler piece adapted to t the concavity in the compressed forepart zone.

Fig. 6 represents a transverse section through 55 the forepart of a shoe wherein the completed insole of the present invention appears withits cushioning pedirme next .tothe .foot- Fig; 7 is 'a' similar view of a shoe wherein the completed insoleof the present invention is shown With its ,cushioning pad lying next to the outsole.

The insole of Fig; l'mayadvantageously consist of fa sheet or base of felted wood'pul'p or other cellulose fibers, such as can be'formed on a paperrmaking machine, impregnated with rubberor other Ielastic binder,y for instance, the r'ubber composition resulting from the drying of a rubber latex composition with which such sheet can be impregnated. The insole in its nished or died-out shape or in the form of an insole blank later to be finished or trimmed to the desired size is punched at its forepart and more particularly at its ball zone to form a multiplicity of openings Iii, which represent voids or bores previously occupied by insole stock and which have been created by the removal of such stock. The insole is then subjected to sufcient pressure at its perforated zone, as in a die-press or rollerpress, to compact such Zone materially, say to one-half of its original thickness, thereby developing a concavity or shallow H at such zone as best Seen in Fig. 4. The desired thinning-out by compaction of the ball zone is facilitated by the perforations l0, which afford ample empty room for the insole stock to be squeezed or crowded as it is being compressed. Indeed, the perforations l0 may become largely, if not completely, closed oif by reason of the compressing or compacting operation but it is usually desirable to control this operation so as to maintain them as relatively much smaller openings l2, thereby fostering ventilation or air circulation through the ball zone.

Into the concavity or shallow Il in the forepart is then placed a cushioning pad or filler piece i3. Such pad or filler piece, which fits accurately into the concavity Il, may be made of sponge rubber, cork composition, or equivalent resiliently compressible material. It may be adhesively secured, as by rubber latex or other suitable aclhesive in position in the concavity Il, which may be preliminarily coated or painted with the adhesive as by brush or other applicator; and, when thus secured, the outer face of the pad preferably projects slightly beyond or outwardly of the face of the insole.

As shown in Fig. 6, the insole hereof is incorporated into a so-called cement-process shoe, but it may be used in shoes made by other methods. In the shoe of Fig. 6J the filler piece I3 is on the foot side, in which case it is preferable to cover the insole with the usual sock-liner l5. Because of the thinned-out condition of the insole stock at the ball zone, the shoe is exible, as is desired, at this yZone and is rendered otherwise comfortable thereat by the cushioning pad. Nevertheless, the margins of the insole are maintained suiciently rigid or stiff for the lasting operation involving the securement or fastening thereto of the marginal or overlasted portion of the shoe upper. The` insole of the present invention is also useful, as illustrated in Fig. 7, with its pad or filler piece I3 lying next to the outsole I6.

The principles of the present invention are applicable in instances involving the perforation of the insole forepart over an area extending beyond the ball zone. Thus, the forepart may be perforated over a zone extending from one vside edge to the other and corresponding to a band of av requires perforation of the insole forepart at least at its ball zone, since it is at this zone in particular that exibilizing and cushioning effects are desired.

It will be understood by those skilled in the art that the present invention may assume embodiments other than those specifically described herein.

I claim:

1. A method of flexibilizing the forepart of an insole at least at its ball zone, which comprises punching the forepart at least at such zone to form multiple openings therein; and compacting the insole stock at such zone to cause it to be displaced into such openings and thereby to alford localized thinner insole stock and a. concavity at such zone.

2. A method of flexibilizing and cushioning the forepart of an insole at least at its ball zone, which comprises punching the forepart at least at such zone to form multiple openings therein; compacting the insole stock at such zone to cause it to be displaced into and close only partially said openings and thereby to afford localized thinner insole stock and a concavity at such zone; and adhesively securing to said forepart Within said concavity a pad yof resiliently compressible material.

FRED L. AYERS. 

